The Firework hitmaker began dating the rocker on and off last summer (12) but they didn't go public with their love until December (12), when they made their first red carpet appearance together.

Mayer opened up about the blossoming relationship during a Tv interview in February (13), when he admitted their bond was "something very human", adding, "I don't feel like I'm in a celebrity relationship. I don't feel it for the first time of my life... I really don't. I'm not even in a high-profile (relationship)... I know it's high-profile, but it's hard to explain. It doesn't feel that way to me and it's great and I'm glad..."

However, it appears his high hopes for lasting love with Perry have fallen flat - UsMagazine.com reports the couple has split, although the break-up may not be permanent.

A source says, "It's sad... It's not over until it's over. You have to see how things play out. (Perry)'s leaving the window open. They have both been so focused on work."

Mayer was Perry's first serious boyfriend since officially divorcing British comedian Russell Brand last year (12).